The enjoyment of a hot beverage such as coffee or tea is dependent on the flavor experienced by the consumer. The flavor sensation for beverages that are served hot is a combination of the actual taste of the beverage and the temperature of the beverage. Although automatic devices for making coffee or hot tea are designed to hold the beverage at a temperature (holding temperature) at which the consumer will experience a desirable flavor sensation, the flavor of the beverage deteriorates if the beverage is maintained at the holding temperature for a period of time, often not more than one hour. The longer the coffee or tea is kept at the holding temperature, the greater the risk that the flavor may become bitter, burned or scorched. One solution to this problem practiced by food service industry is to periodically brew a fresh batch of the beverage. This solution to the flavor problem costs the food service industry time and money since a worker must throw out any beverage not yet consumed and must take the time and use materials to set up and make a "new pot".
Several patents address the problem of preserving the flavor of coffee. U.S. Pat. No. 4,798,937 teaches a plastic covered hot plate having concentric grooves about the center of the hot plate. These groves form open areas through which air can circulate to moderate the temperature of the beverage.
U.S. Pat. No. 5,196,677 teaches a coffee maker having a metal spacer which separates the coffee pot from the hot plate in combination with heat sensing alarms that provides a warning if the level of fluid in the coffee pot is below a set level. The metal spacer has a central opening which provides an air space between the coffee pot and the hot plate to lower the temperature of the coffee.
U.S. Pat. No. 4,994,694 teaches a circular spacer having openings that attenuate the heat that is applied to the coffee pot by the hot plate. This attenuator ring may be attached to the pot or to the hot plate. The attenuator ring works to create an air space between the hot plate and the coffee pot to lower the temperature of the coffee.
The inventors of the present invention wanted to provide a means to keep the flavor of coffee or tea fresh while at the same time maintaining the temperature of the beverage at a high holding temperature which results in the preferred flavor experience for a vast majority of coffee drinkers.